Protesters took to the streets in more than 50 cities today, calling for better wages for fast food workers. Like the Occupy Wall Street movement, these demonstrations target income inequality and promote workers' rights. But today's demonstrators also have one very clearly stated goal. Their demand: $15 an hour wages for workers at, say, McDonald's and Burger King.

NPR's Chris Arnold gives us the picture from Boston.

CHRIS ARNOLD, BYLINE: The press releases for today's action describe workers around the country walking off the job as part of a massive national strike. The reality, though, is definitely less dramatic.

Outside a Burger King this morning in downtown Boston, there were far more organizers than actual striking workers.

ARNOLD: Do you guys know if there are any actual Burger King workers who are out here that I can talk to or...

UNIDENTIFIED FEMALE: I just talked to one of them. He's actually on his way.

ARNOLD: There were representatives from different local community groups, church and labor groups. And there were some Occupy-type folks, too.

Twenty-two-year old Niko Stapczynski(ph) delivers cookies by bicycle for a local bakery.

NIKO STAPCZYNSKI: You know, $8 an hour isn't a living wage. We want benefits for full-time employees and the option to unionize, for sure.

ARNOLD: Stapczynski says he identifies with the struggles of low wage workers, though it turns out his parents are actually still supporting him. That's not so uncommon. Lots of minimum wage workers are younger.

Industry trade groups say the fast food chains offer competitive pay and benefits. And they criticize these protests as theater put on by organized labor. But it's not theater to Kyle King. He's a fast food worker who is skipping work today to attend the protests.

KYLE KING: I work at the Burger King at 128 Tremont Street. I've been employed there nine years, started out at $8 an hour; and now, after nine years, only making 8.15 an hour. So it's just not cutting it at all

ARNOLD: With the cost of rent and other expenses going up, that money, of course, doesn't go as far. King is in his 40's. He lives with his brother. And you can tell he just feels beat-down and tired of working for so long, for so little money.

KING: Just conversations with my brother just paying the bills, because sometimes they'll come and just stick a notice on the door and say the bill is overdue. It's very difficult. They may shut off the electricity sometimes and it's like, oh wow, you know, we can't pay this bill.

ARNOLD: And there is clearly a growing sense of frustration about wages.

LAWRENCE KATZ: Eighty percent of U.S. workers have not seen much of a raise in the 2000s.

ARNOLD: That's Lawrence Katz, a labor economist at Harvard. He says, often by this stage in a recovery wages would be rising. But he says unemployment has stayed high and that lets companies keep wages low, especially for low-skilled work. It's not like most workers can find higher pay elsewhere and even if they do, low-skilled workers are easily replaced.

KATZ: So frustration is understandable but there are also a lot of people who are out of work who envy those who are employed and that creates a very difficult labor market situation.

ARNOLD: Katz says eventually, as the economy comes back, that should help. But can protests like this make any real difference? Katz says actually they can if a movement gets traction. It can then win popular support for things like local living wage ordinances or a bump in the minimum wage.

The protestors today, though, are asking for more than that - $15 an hour. So what might that mean for a fast food business?

SANDEEP MALHOTRA: A typical restaurant would probably have to increase menu prices in the 25 to 30 percent range.

ARNOLD: Sandeep Malhotra is a fast food industry consultant with a company called Technomic. He stresses that this is just ballpark math. But a burger that costs, say, $3 might end up costing closer to $4.

Out on the street, some people said they'd be happy to pay the difference. But Malhotra thinks that other people might not. And he says higher wages might mean more fast food workers get replaced by machines. After all, you already see those automated checkout tellers at CVS and Home Depot.